A new biological activity was discovered for marine fungal meroterpenoid meroantarctine A with unique 6/5/6/6 polycyclic system. It was found that meroantarctine A can significantly reduce biofilm formation by Staphylococcus aureus with an IC of 9.2 µM via inhibition of sortase A activity.
View Article and Find Full Text PDFTen new decalin polyketides, zosteropenilline M (), 11--8-hydroxyzosteropenilline M (), zosteropenilline N (), 8-hydroxyzosteropenilline G (), zosteropenilline O (), zosteropenilline P (), zosteropenilline Q (), 13-dehydroxypallidopenilline A (), zosteropenilline R () and zosteropenilline S (), together with known zosteropenillines G () and J (), pallidopenilline A () and 1-acetylpallidopenilline A (), were isolated from the ethyl acetate extract of the fungus KMM 4679 associated with the seagrass . The structures of isolated compounds were established based on spectroscopic methods. The absolute configurations of zosteropenilline Q () and zosteropenilline S () were determined using a combination of the modified Mosher's method and ROESY data.
View Article and Find Full Text PDFFour extracts of the marine-derived fungus Penicillium velutinum J.F.H.
View Article and Find Full Text PDFThe marine-derived fungal strains KMM 4718 and KMM 4747 isolated from sea urchin as a natural fungal complex were identified as and based on Internal Transcribed Spacer (), partial β-tubulin (), and calmodulin () molecular markers as well as an ribosomal polymerase two, subunit two () region for KMM 4747. From the ethyl acetate extract of the co-culture, two new polyketides, sajaroketides A () and B (), together with (2'S)-7-hydroxy-2-(2'-hydroxypropyl)-5-methylchromone (), altechromone A (), norlichexanthone (), griseoxanthone C (), 1,3,5,6-tetrahydroxy-8-methylxanthone (), griseofulvin (), 6-O-desmethylgriseofulvin (), dechlorogriseofulvin (), and 5,6-dihydro-4-methyl-2H-pyran-2-one () were identified. The structures of the compounds were elucidated using spectroscopic analyses.
View Article and Find Full Text PDFFive new β-resorcylic acid derivatives, 14-hydroxyasperentin B (), β-resoantarctines A-C (, , ) and 8-dehydro-β-resoantarctine A (), together with known 14-hydroxyasperentin (5'-hydroxyasperentin) (), were isolated from the ethyl acetate extract of the fungus KMM 4685 associated with the brown alga . The structures of the compounds were elucidated by spectroscopic analyses and modified Mosher's method, and the biogenetic pathways for compounds - were proposed. For the very first time, the relative configuration of the C-14 center of a known compound was assigned via analyses of magnitudes of the vicinal coupling constants.
View Article and Find Full Text PDFNew meroterpenoids, meroantarctines A-C (-), with unique 6/5/6/6, 6/5/6/5/6, and 6/5/6/5 polycyclic systems were isolated from the alga-derived fungus KMM 4685. Their structures were elucidated by spectroscopic methods, X-ray diffraction, and quantum chemical calculations. A biogenetic pathway for - was proposed.
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